Nanotech News

September 2013

New Insights into Hyperthermia Cancer Therapy

Magnetic hyperthermia is viewed as an attractive approach for the treatment of certain cancers as it has no known side effects compared to more conventional therapies such as chemotherapy. It is particularly suitable for the treatment of prostate cancer and brain tumors. However, until now there has been no clear theoretical understanding of how it actually works. In a paper published in the Journal of Physics D: Applied Physics, a team of investigators led by Kevin O’Grady from the University of York have shown that the amount of heat generated by magnetic nanoparticles can be understood when both the physical and hydrodynamic size distributions for the samples are known to high accuracy.

Treatment by magnetic hyperthermia involves injecting magnetic nanoparticles directly into a tumor then placing the patient in a machine which produces an alternating magnetic field. The nanoparticles oscillate and heat is produced inside the tumor tissue. When the temperature rises above 42 degrees Celsius cells begin to die, and research has shown that this heating process reduces tumor size.

Prior to this work, researchers had no way of predicting how much heat would be generated by a given nanoparticle formulation. The key to identifying and quantifying the mechanisms involved in heat generation was the use of magnetic particles of highly uniform and well-defined size that do not stick to one another. The researchers note that their modeling and experimental work provide the means to calculate accurately the dose of magnetic nanoparticles and the length of treatment required to produce a desired level of heating.

This work is detailed in a paper titled, “Mechanisms of hyperthermia in magnetic nanoparticles.” Investigators from the Welsh company, Liquids Research Ltd., which created the nanoparticles used in this study also participated in this research. An abstract of this paper is available at the journal’s website.